SCHOTT solutions no. 1/2012 > Design

Dimples in the glass provide a sense of orientation on how to operate the electric switches and complement the displays and touchscreens used in high-quality appliances. Photo: SCHOTT/C. Costard

Glassy Trademark

The way in which we operate electronic devices is changing. Now, SCHOTT® Smart Touch makes it possible to create devices with tactile switch buttons on a glass surface – and therefore offers potential for design and advanced user interfaces.

Judith Schwarz

Regardless of whether it’s our coffee machines, hi-fi systems or refrigerators, the electronic devices we used to operate by pressing buttons made of metal or plastic are now being ­replaced by smooth, homogeneous control panels. The trend is towards minimalist designs and glassy surfaces.

Users rely on orientation guides to help them find the right functions on these uniform surfaces quickly and safely. Slight indentations in what are otherwise smooth glass surfaces allow people to feel these. The main advantage they offer is that the operator can detect them intuitively – this is particularly helpful for people who have poor eyesight. In addition, glass control panels are also much easier to clean than buttons: the surface is sealed off tightly and glass stands up well to aggressive cleaning agents. This ensures better hygiene in medical devices, for instance. And, last but not least, these modern control elements look very attractive – at least if the indentations have been carefully engraved in the glass.

When used together with a capacitive switch, a slider offers linear control of the functions in an electric appliance. Photo: SCHOTT/C. Costard

Precision in glass

The most difficult thing about manufacturing them is how to place SCHOTT® Smart Touch on the glass pane this accurately. A manufacturing process developed by SCHOTT now overcomes this challenge and allows for a much greater variety of shapes and sizes. A special machine holds the precisely cut glass pane in place and allows for precise positioning of the grinding point with a tolerance of only plus/minus 0.05 to 0.2 mm – depending on the size of the glass pane and the overall requirements. SCHOTT® Smart Touch can be made to look either matte or polished – with the shiny appearance so typical of glass.

Manufacturers of electronic appliances find it very easy to attach switches behind these types of glass panels. Precise placement of the grinding points in the same places during serial production makes this a lot easier. The possibilities range from capacitive circuits to active or passive infrared technology or acoustic wave technology. The operator simply places his finger on the indentations to regulate or turn these appliances on and off.

This also results in a wide range of different options from a design point of view. Among other things, SCHOTT is able to produce these indentations as a ring or strip with rounded corners. Indentations can be made in all types of flat glasses of preferably between 2 and 10 mm in thickness. Lighting and printing that includes colors and symbols produces an even greater variety. This technology thus offers appliance and electronics manufacturers the chance to provide truly personal operation. In this way, the versatile material of glass can enable them to stand out from the crowd by using original designs and therefore sharpen their own brand identity. <|